Finding equivalent semiconductors -any websites?

Not exactly for hard-to-find; but here is one :

----> http://nte01.nteinc.com/nte\NTExRefSemiProd.nsf/$all/72BF14B50722ACF285257910007E5A0D?OpenDocument

 

Sir TTL . . . . .

Expounding further upon the Right Revered and Most Honnable External -nets info . . . .
(¿Que paaaaaaaaaaaaasssssssssa?)

There used to be a cross reference put out by just about every semiconductor manufacturer, with the General Electric’s GE line, the Motorola’s HEP line and RCA’s SK line and lastly the Sylvanias ECG series of Semiconductors.

Seems like that last surviving, now defunct ECG series has been adapted into the NTE product line with the same numbering that ECG had used, but with incorporation of a NTE prefix.

The Sharp PA900 of pre 1990’s developmental timeframe is still alive and available.

HOWEVER, they also re-released a faster digital friendly version in the 2000’s .

Perhaps that is your problem, in the respect of needing a “faster” version of the original, basically darlington "bare bones" technology style design of the original unit, should you be involved in faster digital work or musical or higher frequency audio processing, involving a fast schmitt triggering response.

They are still being available on the cheeeeep at

https://www.utsource.net/ic-datasheet/PC900-1386619.html

As the original PC900V at a professed 0.21 cents a copy
OR most importantly,as a:
PC900VONSZXF . . .digital speed version at 0.30 cents a copy

SHARP;s DA-DA Sheet:
http://www.sharp-world.com/products/device/lineup/selection/opto/pc/opic_3.html

73’s de Edd

 

It will be plug in backwards compatible or they woud have changed its designation.